<html>
<script>
    function User(){
        console.log("user")
    }

    User.prototype.sayHello = ()=>{
        console.log("你好prototype")
    }

    User.__proto__.sayHello = ()=>{
        console.log("你好__proto__")
    }

    let user1 = new User()
    user1.sayHello()
    User.sayHello()

    console.dir(user1)
    console.dir(User)
</script>
</html>